Jobridge

ABSTRACT

The Jobridge is a portable bridge that is used to cross over grade beams or other obstacles on a construction site. It is constructed of 6061 aluminum to allow it to be lifted and moved with light machinery or equipment. It is coated with a non-slip coating that is safety yellow. The Jobridge is rated for a maximum weight load of 12,000 lbs. To cross the Jobridge the equipment must be 12,000 lbs or less and the tracks must be 8 ft wide or less. Obstacles that are traversed must be less than 30 inches wide and less than 13 inches tall in the center. The Jobridge is more suited for crossing buried, or partially buried, obstacles or narrow trenches like grade beams. The intent is to prevent damage to the grade beam side wall (obstacle) or steel reinforcements that may protrude from the grade beam.

CROSS REFERENCE TO RELATED APPLICATIONS

Not applicable.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not applicable.

REFERENCE TO SEQUENCE LISTING, A TABLE, OR A COMPUTER PROGRAM LISTING COMPACT DISK APPENDIX

Not applicable.

BACKGROUND OF THE INVENTION

While on a jobsite I witnessed a problem that persists between many other jobsites. Workers and equipment must travel through and work within foundations after the grade beams are dug. This presents a mobility problem. The equipment is needed to haul things into the areas where workers are present, or to dig and backfill trenches for utilities. There are cases when the grade beams are poured and there is then rebar that sticks out of the concrete. Rebar is bent and tied into shapes that have been designed and approved by structural engineers. It must maintain its proper shape. In these cases, the rebar gets smashed down by equipment tracking over it to get where it is needed. The rebar is then required to be repaired. This repair work is in excess of what contractors bid for and budget for when it comes to labor hours. If there were something, they could use to cross over these grade beams without ruining them it would prevent a lot of wasted capital and time. This something should be strong enough to carry the weight of equipment and people.

BRIEF SUMMARY OF THE INVENTION.

Based upon the problem outlined in section [005], I decided that the simplest solution would be to design a tiny lightweight bridge that could be moved around to different positions within a slab work area. This would not be too difficult a task using standard structural shapes. Since it needs to be portable and compact, I decided to use a truss design. To further reduce the weight, I decided to use aluminum extrusions as the material of construction. Based on my experience I decided that I would design one standard version for a specific weight load that would cover most applications. If a customer needs something stronger it will need to be engineered and built for their specific need. Customers may also use the invention for crossing other things such as small ditches, pipes, and electrical lines so long as they fit under the Jobridge, in the designated pass through for obstacles, without touching it. It shall have a rectangular section through the center that is open for pass through of obstacles.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

FIG. 1 —an isometric view of the entire assembly

FIG. 2 —a front view of the entire assembly

FIG. 3 —a front view of the assembly with the tread plates removed

FIG. 4 —a right side view with the treadplates removed

FIG. 5 —an isometric view from the bottom with the treadplates removed

FIG. 6 —a bottom view with the treadplates removed

FIG. 7 —a top view with the treadplates removed

FIG. 7A—a section view with the treadplates removed

FIG. 8 —an isometric view of the flat bar slats (2)

FIG. 9 —a front view of the flat bar slats

FIG. 10 —an isometric view of the angles (5) that reinforce the slats

FIG. 11 — a front view of the angle

FIG. 12 —a right side view of the angle

FIG. 13 —an isometric view of the center treadplate (3)

FIG. 14 —a bottom view of the center treadplate

FIG. 15 —a right side view of the center treadplate

FIG. 16 —an isometric view of the side treadplates (4)

FIG. 17 —a bottom view of the side treadplates

FIG. 18 —a right side view of the side treadplates

FIG. 19 —an isometric view of the lifting lugs (6)

FIG. 20 —a front view of the lifting lugs

FIG. 21 —a right side view of the lifting lugs

FIG. 22 —an isometric view of the truss (1)

FIG. 23 —a back view of the truss

FIG. 24 —a top view of the truss

FIG. 25 —a dimensioned back view of the truss

FIG. 26 —a right side view of the truss

DETAILED DESCRIPTION OF THE INVENTION

The Jobridge is a new invention that is intended to make moving light equipment, such as skid steers and miniature excavators, within a foundation work site easier. By using a Jobridge, a contractor can effectively reduce or eliminate damage to the foundation grade beam trenches, steel reinforcements, plumbing, and electrical conduits. This will prevent the contractor from having to spend time and money they did not budget for on repairs. It is called the Jobridge because it behaves like a tiny bridge and is used on jobsites.

There is but one similar product that I am aware of. It is called the “Brahman System(s).” However, the scope of use is different. The Brahman is a device used in road crossings when there are hoses or electrical wires going over the road during construction or temporary re-routes of fluids or electricity. It is made from steel and is rated for much heavier loads. The Brahman cannot accomplish what the Jobridge can on a construction site. With a Jobridge a piece of equipment can cross over form boards without having to remove them. Then a mini excavator could be used to lift the Jobridge and move it to another place inside the forms where the equipment needs to cross over another obstacle. The Jobridge allows small equipment to play leapfrog with obstructions on a job site, primarily with new foundation construction phases. The Brahman has a small trough going through the center with a lid for the hoses or electrical wires to pass through it. The Jobridge has a raised center section allowing obstructions to pass under it or for the Jobridge to be placed over the obstruction.

To fabricate the Jobridge, one will need a welding table or jig that is flat, level with grade, and square. The table will need to be at least 8 feet in length or width. One will also need a welding machine that is capable of welding aluminum. The craftsman will also need tools to measure, level, cut, clamp, sand, and grind the work pieces. Once fabricated the Jobridge will need to be put in a spray booth and coated with a rubberized non-slip coating that is safety yellow in color. This is not meant to be an exhaustive list of tools and equipment, but more of an advisory that the Jobridge should be fabricated by skilled professionals that have this equipment and use it regularly.

The fabrication will need to start with building the four trusses. I will describe assembly of one truss, and this will be applicable to all four. Start with two aluminum 6061 T6 AISC C3×3.5 33 in long. Place them with the open side down on the work surface. They must be parallel to each other and the inside ends must be 30 in apart. This is shown in FIG. 25 on page 11 of the drawings. A part 19 cap plate is to be welded on the outside facing ends of the c channels.

Then, on each c-channel add the vertical members 11, 10, 9, and 8. There will be two of each, one for each side. These members are aluminum 6061 T6 AISC 2×1.5×3/6 rectangular tubes. Their locations can be seen in FIGS. 23 and 25 . Their lengths can be found in both the table on page 9 and in FIG. 25 on page 11. The angle on the top edge that they are cut on is 20° from the horizontal plane. Ensure that each of these vertical members is squared and held at 90° from the c-channel and in their proper locations. Weld each of these vertical members with a full penetration weld around the base such that they are completely joined to each of the respective c-channels.

Now add member 12 between the two, vertical member 8 s. Member 12 is made from the same rectangular tubing as the member 8 s and is 30 in long. Member 12 must be squared and held 90° from the member 8 s. Member 12 must also be held flush with the tallest edge of the member 8 s. Member 12 is to be welded on each end to the member 8 s with full penetration welds.

Installing the two, part 14 s may seem intimidating, however it is not difficult. Part 14 is an AISC L 1.5×1.5×3/16 6061 T6 aluminum angle. Use the cut length provided in the table to cut the pieces. To figure the angle cuts you will place them on top of the member 12 and 8 s. Position them so that they are 20° from the horizontal member 12. Mark the angles you need to cut to make the pieces fit. Now weld them on each end. One end to member (part) 12 and one end to part 8.

A similar process will be used to install the two, part 13 s. Part 13 is an AISC L 2.5×1.5×3/16 6061 T6 aluminum angle. Cut the two pieces to the length shown. Place them such that the inside surfaces are contacting all of the vertical tubes. The end that is over part 8 will need to be flush to the edge of part 8 that is welded to part 14. Mark the angles needed on each end of the part 13 s. The angle on the end contacting part 7 should be a 20° angle as measured from the inside surface of the short leg of the L shape. See FIG. 25 . Once you have these parts cut and positioned, they will need to be welded to parts 7, 8, 9, 10, and 11 with full penetration welds.

Next install parts 15, 16, 17, and 18. There are 2 of each. The cut lengths of each are shown in the parts list. These parts are all AISC L 1.5×1.5×3/16 6061 T6 aluminum angles. These parts will complete the truss by adding reinforcement to the vertical members. In a process similar to the other angled pieces, place them on top of the space you will put them. They will partially rest on top of the vertical members, part 13 and part 7. The ends will need to go from corner to corner diagonally, or as close as they will reach. Mark the angles that need to be cut on the ends. For part 18, the piece will go from the corner of where part 11 meets part 7 to the center of that section of part 13. These pieces will be welded to the vertical members, part 7, and part 13 where they touch respectively. The welds shall be full penetration where possible, but otherwise they will be fillet welds.

Once 4 trusses have been made, it is time to begin building the overall assembly. Stand the 4 trusses up vertically such that they are resting on both sides of the c channels as shown in FIGS. 4, 5 , and 6 on page 2. All 4 must be parallel with each other and spaced 30.08 in apart. Use four, part 2 s to join the trusses together across the c channels. See FIG. 7A for the location of the part 2 s. There will be 2 on each side. Weld the part 2 s to the c channels. Part 2 is aluminum flat bar 0.25×2×95.75 in.

There are 11 more, part 2 s. These will be welded across the top of the trusses. They will all be parallel with each other and perpendicular to the trusses. The locations are shown in FIG. 7A. There are four on each of the sloped sides and three in the center section. The parts at the top of the sloped sections are flush with the end of the part 13 s. Likewise, the part 2 s at the ends of the center section are flush with the edges of part 12. Part 2 can also be seen in FIGS. 8 and 9 .

Once the part 2 s are done add the part 5 s. Each part 5 is welded to the underside of the part 2 s attached to parts 12 and 13. They are located between the trusses and also weld to the trusses. This can be seen in FIG. 7A as well. The FIGS. 10 through 12 show this part in isolation. Part 5 is an AISC 2×2×3/16 in 6061 T6 aluminum angle.

Now parts 3 and 4 can be added. There is one, part 3 and two, part 4 s. Part 3 can be seen in FIGS. 13 through 15 . Part 4 can be seen in FIGS. 16 through 18 . These parts are made from aluminum treadplate or diamond plate that is 0.188 in thick. Part 3 will cover the center section of the Jobridge, and part 4 will cover each sloped side of the Jobridge. These plates will be welded to the structure where they contact by stitch welding on the underside and fully welded across the outside edges and the seams between them.

Part 6 is the last part to be added on. The two, part 6 s are the lifting lugs. It can be seen in FIGS. 19 through 21 . Each part 6 is located in the center of the outside part 12 s. This can be seen in FIGS. 1 through 5 . They will be attached to the part 12 s by full fillet welds. The vertical legs of the weld shall be uphill welds. The lifting lugs are made from 0.5 in thick 6061 aluminum plate.

The last step in construction is the coating. The Jobridge is to be painted safety yellow with a high durability coating. The top surfaces shall be coated in safety yellow rubberized coating such as Line-X, Rhino Liner, or equivalent. Striping with black chevrons is also acceptable.

To use the Jobridge, one will need a mini excavator or skid steer weighing 12,000 lbs or less. If using a skid steer, it must have forks or another attachment for lifting things. The outside dimension of the tracks or tires must be 8 ft or less. The excavator or skid steer will be referred to as “the equipment” or “equipment.” Use the lifting lugs to attach the rigging of your choice. It may be nylon straps, cables, chains, or ropes. Attach the rigging to the bucket of the mini excavator or the lifting point on the skid steer attachment. Use the equipment to lift the Jobridge. Track over to the obstacle that you need to cross. Slowly lower the Jobridge over the top of the obstacle until it is contacting the ground on both sides of the obstacle. Detach the rigging from the equipment and the Jobridge. Track over the Jobridge with the equipment carefully, making sure not to go off the edge of the Jobridge. Once the equipment is on the other side of the obstacle and no longer contacting the Jobridge, it can be rigged for lifting again and either moved out of the way or used again to cross another obstacle.

Notice: There is a risk for equipment roll over while using this product. The user assumes all responsibility for damage to equipment, injury, or death in the use of the Jobridge. A properly sized piece of equipment will reduce the chance of this happening. Further reduction to risk will be achieved by using a competent, trained, and certified operator. The use of a flag man is highly recommended while using the Jobridge. 

1. The invention shall be called the Jobridge.
 2. The main purpose of the Jobridge is to facilitate crossing grade beams within a foundation work site. a. The Jobridge may be used by people or light equipment such as skid steers or miniature excavators up to 12,000 lbs. b. The Jobridge has a weight rating of 12,000 lbs with a 2.5 safety factor.
 3. The Jobridge may also be used for crossing other small trenches, but the Jobridge must have at least 3A of its foundation, on each side, in contact with solid ground.
 4. The Jobridge may be used to facilitate crossing over pipes or electrical lines. a. The electrical lines and pipes passing under the Jobridge must not contact the structure of the Jobridge.
 5. The Jobridge has a hollow section through the center to allow obstructions to pass under it without contacting them. a. This hollow section shall be 2.5 feet wide, 13 inches tall, and pass through the entire width of the Jobridge.
 6. The Jobridge shall be constructed of 6061 T6 aluminum extrusions and treadplate with a non-slip coating. a. The non-slip coating shall be safety yellow.
 7. The Jobridge shall have permanently affixed lifting points so that it may be raised and lowered with machinery.
 8. The Jobridge may be carried into the work area by construction equipment, set in its designated place, crossed, lifted again, and moved to another place that needs to be crossed. a. It may also be left in a designated place for semi-permanent use. b. Semi-permanent refers to the duration of the work being done in the construction area. 